Effect of debittering and solid‐state fermentation processes on the nutritional content of lupine (<i>Lupinus mutabilis</i> Sweet)
Elena Villacrés, María Belén Quelal, Xiomara Jácome, Gabriela Cueva, Cristina M. Rosell
Abstract
Summary There is a growing interest in vegetable‐based sources of proteins. Despite its high nutrient content, lupine has been rarely exploited as a protein source due to the presence of high levels of non‐nutritive compounds such as alkaloids, which impart a bitter taste. Here, we evaluated the effect of debittering and solid‐state fermentation on the nutritional contents of three lupine varieties ( Lupinus mutabilis Sweet). These processes induced significant changes ( P < 0.05) in the nutritional composition of the three lupine varieties (INIAP‐450, INIAP‐451 and Criollo) and increased the protein levels to 644.55 g kg −1 (Criollo variety) and the levels of several constituent amino acids such as valine (54.62 g kg −1 ), methionine (42.47 g kg −1 ), isoleucine (59.27 g kg −1 ) and leucine (76.32 g kg −1 ). The ether extract of INIAP‐450 showed increased levels (up to 244.03 g kg −1 ); especially, monounsaturated fatty acids (559.78 g kg −1 ) and polyunsaturated fatty acids (293.17 g kg −1 ) were observed. The omega‐6/omega‐3 ratio in the debittered grain oil reached the minimum requirement established for good‐quality oils (5/1). However, the levels of other components decreased, showing levels up to 13.04 g kg −1 (total starch) in the Criollo variety, 22.62 g kg −1 (resistant starch) in INIAP‐450, 6.53 g kg −1 (potassium) in INIAP‐451, 46 g kg −1 (iron) in INIAP‐451 and 29.75 g kg −1 (zinc) in INIAP‐450.